Reference "Classification and characterization of the rice alpha-amylase family"

Reference ID

1521

Title

Classification and characterization of the rice alpha-amylase family

Source

Plant molecular biology, 1990, vol. 14, pp. 655-668

Authors (4)

Huang-N	Sutliff-T-D
Litts-J-C	Rodriguez-R-L

Abstract

To establish the size and organization of the rice alpha-amylase multigene
family, we have isolated 30 alpha-amylase clones from three independent genomic
libraries. Partial characterization of these clones indicates that they fall
into 5 hybridization groups containing a total of 10 genes. Two clones belonging
to the Group 3 hybridization class have more than one gene per cloned fragment.
The nucleotide sequence of one clone from Group 1, lambda OSg2, was determined
and compared to other known cereal alpha-amylase sequences revealing that lambda
OSg2 is the genomic analog of the rice cDNA clone, pOS103. The rice alpha-
amylase genes in Group 1 are analogous to the alpha-Amy1 genes in barley and
wheat. lambda OSg2 contains sequence motifs common to most actively transcribed
genes in plants. Two consensus sequences, TAACAAGA and TATCCAT, were found in
the 5' flanking regions of alpha-amylase genes of rice, barley and wheat. The
former sequence may be specific to alpha-amylase gene while the latter sequence
may be related to a 'CATC' box found in many plant genes. Another sequence
called the pyrimidine box (TCCTTTTTC) was found in the alpha-amylase genes as
well as other genes regulated by gibberellic acid (GA). Comparisons based on
amino acid sequence alignment revealed that the multigene families in rice,
barley and wheat shared a common ancestor which contained three introns. Some of
the descendants of the progenitor alpha-amylase gene appear to have lost the
middle intron while others maintain all three introns.